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Merozoites
Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism is typified by a ''cellular variety'' with a distinct morphology and biochemistry. Not all apicomplexa develop all the following cellular varieties and division methods. This presentation is intended as an outline of a hypothetical generalised apicomplexan organism. Methods of asexual replication Apicomplexans (sporozoans) replicate via ways of multiple fission (also known as schizogony). These ways include , and , although the latter is sometimes referred to as schizogony, despite its general meaning. Merogony is an asexually reproductive process of apicomplexa. After infecting a host cell, a trophozoite ( see glossary below) increases in size while repeatedly replicating its nucleus and other organelles. During this process, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxoplasma Gondii
''Toxoplasma gondii'' () is a species of parasitic alveolate that causes toxoplasmosis. Found worldwide, ''T. gondii'' is capable of infecting virtually all warm-blooded animals, but members of the cat family (felidae) are the only known definitive host#Hosts to parasites, definitive hosts in which the parasite may undergo sexual reproduction. In rodents, ''T. gondii'' Behavior-altering parasites and parasitoids, alters behavior in ways that increase the rodents' chances of being Predation, preyed upon by felids. Support for this "manipulation hypothesis" stems from studies showing that ''T. gondii''-infected rats have a decreased aversion to cat urine while infection in mice lowers general anxiety, increases explorative behaviors and increases a loss of aversion to predators in general. Because cats are one of the only hosts within which ''T. gondii'' can sexually reproduce, such behavioral manipulations are thought to be Adaptation, evolutionary adaptation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merogony
Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism is typified by a ''cellular variety'' with a distinct morphology and biochemistry. Not all apicomplexa develop all the following cellular varieties and division methods. This presentation is intended as an outline of a hypothetical generalised apicomplexan organism. Methods of asexual replication Apicomplexans (sporozoans) replicate via ways of multiple fission (also known as schizogony). These ways include , and , although the latter is sometimes referred to as schizogony, despite its general meaning. Merogony is an asexually reproductive process of apicomplexa. After infecting a host cell, a trophozoite ( see glossary below) increases in size while repeatedly replicating its nucleus and other organelles. During this process, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmodium
''Plasmodium'' is a genus of unicellular eukaryotes that are obligate parasites of vertebrates and insects. The life cycles of ''Plasmodium'' species involve development in a Hematophagy, blood-feeding insect host (biology), host which then injects parasites into a vertebrate host during a blood meal. Parasites grow within a vertebrate body tissue (often the liver) before entering the bloodstream to infect red blood cells. The ensuing destruction of host red blood cells can result in malaria. During this infection, some parasites are picked up by a blood-feeding insect (mosquitoes in majority cases), continuing the life cycle. ''Plasmodium'' is a member of the phylum Apicomplexa, a large group of parasitic eukaryotes. Within Apicomplexa, ''Plasmodium'' is in the order Haemosporida and family Plasmodiidae. Over 200 species of ''Plasmodium'' have been described, many of which have been subdivided into 14 subgenera based on parasite morphology and host range. Evolutionary relations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Babesia
''Babesia'', also called ''Nuttallia'', is an apicomplexan parasite that infects red blood cells and is transmitted by ticks. Originally discovered by Romanian bacteriologist Victor Babeș in 1888; over 100 species of ''Babesia'' have since been identified. ''Babesia'' comprises more than 100 species of tick-borne parasites that infect erythrocytes (red blood cells) in many vertebrate hosts. ''Babesia'' species infect livestock worldwide, wild and domestic vertebrate animals, and occasionally humans, where they cause the disease babesiosis. In the United States, ''B. microti'' is the most common strain of the few that have been documented to cause disease in humans. Classification ''Babesia'' is a protozoan parasite found to infect vertebrate animals, mostly livestock mammals and birds, but also occasionally humans. Common names of the disease that ''B. microti'' causes are Texas cattle fever, redwater fever, tick fever, and Nantucket fever. The disease it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apicomplexa
The Apicomplexa (also called Apicomplexia; single: apicomplexan) are organisms of a large phylum of mainly parasitic alveolates. Most possess a unique form of organelle structure that comprises a type of non-photosynthetic plastid called an apicoplastwith an apical complex membrane. The organelle's apical shape is an adaptation that the apicomplexan applies in penetrating a host cell. The Apicomplexa are unicellular and spore-forming. Most are obligate endoparasites of animals, except '' Nephromyces'', a symbiont in marine animals, originally classified as a chytrid fungus, and the Chromerida, some of which are photosynthetic partners of corals. Motile structures such as flagella or pseudopods are present only in certain gamete stages. The Apicomplexa are a diverse group that includes organisms such as the coccidia, gregarines, piroplasms, haemogregarines, and plasmodia. Diseases caused by Apicomplexa include: * Babesiosis ('' Babesia'') * Malaria (''Plasmodium'') * Cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gametocyte
A gametocyte is a eukaryotic germ cell that divides by mitosis into other gametocytes or by meiosis into gametids during gametogenesis. Male gametocytes are called ''spermatocytes'', and female gametocytes are called ''oocytes''. Development The development of gametogonia to primary gametocytes is called gametocytogenesis. The further development of primary gametocytes to secondary gametocytes is a part of gametidogenesis. Gametogenesis is the formation or production of gametes (taking place during meiosis). The development and maturation of sex cells also takes place during meiosis. Gametogenesis is also the process of formation in male and female gametes that occur in the gonads (ovary and testis). Both male and female produce gametes. Male gametocytes are called spermatocytes and female gametocytes are called oocytes. The term gametocyte is also used, for example, when talking about gametocytes of species like ''Plasmodium falciparum'' or ''Plasmodium vivax'', which transmit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apicomplexa
The Apicomplexa (also called Apicomplexia; single: apicomplexan) are organisms of a large phylum of mainly parasitic alveolates. Most possess a unique form of organelle structure that comprises a type of non-photosynthetic plastid called an apicoplastwith an apical complex membrane. The organelle's apical shape is an adaptation that the apicomplexan applies in penetrating a host cell. The Apicomplexa are unicellular and spore-forming. Most are obligate endoparasites of animals, except '' Nephromyces'', a symbiont in marine animals, originally classified as a chytrid fungus, and the Chromerida, some of which are photosynthetic partners of corals. Motile structures such as flagella or pseudopods are present only in certain gamete stages. The Apicomplexa are a diverse group that includes organisms such as the coccidia, gregarines, piroplasms, haemogregarines, and plasmodia. Diseases caused by Apicomplexa include: * Babesiosis ('' Babesia'') * Malaria (''Plasmodium'') * Cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygote
A zygote (; , ) is a eukaryote, eukaryotic cell (biology), cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information of a new individual organism. The sexual fusion of haploid cells is called karyogamy, the result of which is the formation of a Ploidy#Haploid and monoploid, diploid cell called the zygote or zygospore. History German zoologists Oscar Hertwig, Oscar and Richard Hertwig made some of the first discoveries on animal zygote formation in the late 19th century. In multicellular organisms The zygote is the earliest developmental stage. In humans and most other Anisogamy, anisogamous organisms, a zygote is formed when an egg cell and sperm, sperm cell come together to create a new unique organism. The formation of a cell potency, totipotent zygote with the potential to produce a whole organism depends on epigenetics, epigenetic reprogramming. DNA demethyla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Blood Cell
Red blood cells (RBCs), referred to as erythrocytes (, with -''cyte'' translated as 'cell' in modern usage) in academia and medical publishing, also known as red cells, erythroid cells, and rarely haematids, are the most common type of blood cell and the vertebrate's principal means of delivering oxygen () to the body tissue (biology), tissues—via blood flow through the circulatory system. Erythrocytes take up oxygen in the lungs, or in fish the gills, and release it into tissues while squeezing through the body's capillary, capillaries. The cytoplasm of a red blood cell is rich in hemoglobin (Hb), an iron-containing biomolecule that can bind oxygen and is responsible for the red color of the cells and the blood. Each human red blood cell contains approximately 270 million hemoglobin molecules. The cell membrane is composed of proteins and lipids, and this structure provides properties essential for physiological Cell (biology), cell function such as erythrocyte deformabil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccidiosis
Coccidiosis is a parasitic disease of the intestinal tract of animals caused by coccidian protozoa. The disease spreads from one animal to another by contact with infected feces or ingestion of infected tissue. Diarrhea, which may become bloody in severe cases, is the primary symptom. Most animals infected with coccidia are asymptomatic, but young or immunocompromised animals may suffer severe symptoms and death. While coccidia can infect a wide variety of animals, including humans, birds, and livestock, they are usually species-specific. One well-known exception is toxoplasmosis caused by '' Toxoplasma gondii''. Humans may first encounter coccidia when they acquire a dog, cat or bird that is infected. Other than ''T. gondii'', the infectious organisms are canine and feline-specific and are not contagious to humans, unlike the zoonotic diseases. Coccidia in dogs Puppies are frequently infected with coccidia from the feces of their mother, and are more likely to develop cocc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intracellular Parasite
Intracellular parasites are microparasites that are capable of growing and reproducing inside the cells of a host. They are also called intracellular pathogens. Types There are two main types of intracellular parasites: Facultative and Obligate. Facultative intracellular parasites are capable of living and reproducing in or outside of host cells. Obligate intracellular parasites, on the other hand, need a host cell to live and reproduce. Many of these types of cells require specialized host types, and invasion of host cells occurs in different ways. Facultative Facultative intracellular parasites are capable of living and reproducing either inside or outside cells. Bacterial examples include: Fungal examples include: Obligate Obligate intracellular parasites cannot reproduce outside their host cell, meaning that the parasite's reproduction is entirely reliant on intracellular resources. All viruses are obligate intracellular parasites. Bacterial examples (that affect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
